Finding the Fourth Proportional to 1,308.68, 1,806.72 and 811.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,308.68 : 1,806.72 = 811.52 : x
2. Step 2: Convert to fraction form
   1,308.68/1,806.72 = 811.52/x
3. Step 3: Cross multiply
   1,308.68x = 1,806.72 × 811.52
4. Step 4: Simplify right side
   1,308.68x = 1,466,189.41
5. Step 5: Solve for x
   x = 1,466,189.41/1,308.68
6. Step 6: Final answer
   x = 1,120.36